the beginning. ♪ ♪ this is a stunning workoftechnology. ♪this is the 2013 lexus es and the first-ever es hybrid. this is the pursuit of perfection. >>> the mayhem began last night. they shot the m.i.t. police officer in the head and killed him. the suspects carjacked a mercedes suv. >> there is a massive manhunt under way. we're asking people to shelter in place. in other words, to stay indoors. >> that pursuit ended up in watertown, massachusetts. a massive dragnet has ensued. >> officials apparently on the lookout for some accomplices other than the suspects that are related to the bombing itself. >> they were also looking for another suspect who they believed may have hopped on an amtrak train south toward connecticut. they did not find anyone on that train. they do not know if this person still has any explosives or what might happen. >> just heard the uncle of the suspects obviously distancing himself from the individuals themselves. >> i say if you're alive, turn yourself in and ask for forgiveness. >> welcome back to cnbc. breaking news. want to take you to a live picture of fenwa